Not one but two tech acquisitions were announced by Google (NSDQ: GOOG) today: Apture and Katango, both of which point to Google’s ambition to make its user experience more sophisticated as the company matures.

Financial terms for both deals were not disclosed.

In both cases, the acquisitions look like they have been made to specifically enhance existing Google products.

Katango started its public life only just this past summer as an iPhone app to manage a user’s Facebook contacts, automatically creating lists that could receive targeted status updates or other messages without those messages being broadcast to the whole contact list. (Those contacts with the app would get them pushed automatically; those without would get the updates by text, email or the next time they logged into Facebook.)

Apture, meanwhile, is a relative old-timer, being established in 2008. Over the past few years, the company has built up a two-pronged business: the first a focused around a browser extension that lets users perform automatic searches on words on web pages; the second a white-label service: content companies could incorporate this feature directly on to their web pages to keep users from migrating away on the hunt for further information on a topic; or they could add in some code to their site so that Apture could create hyperlinks and in-page browsing of those links automatically.

If the idea of Katango’s automatic lists sounds familiar to you but you’ve never heard of Katango, it might be because Facebook, just months later, introduced nearly the same feature as part of Facebook. It calls the service “Smart Lists.”

That made Katango less relevant for Facebook but potentially more attractive for Google — which has been building up a Facebook competitor, Google+, but without a similar service to group people into specific social circles automatically (currently a user has to categorize contacts into social circles manually).

Although Katango started life as a mobile app it looks like this next chapter will be about enhancing the more general online experience. Its home page notes that the Katango folks will be joining the Google+ product team to enhance the Circles feature, presumably with its automating technology:

“We’re excited to join the Google+ team…Google+ is seeing tremendous momentum, so it’s a perfect time to join and make Circles smarter for millions of people.”

And, as with so many acquisitions by large companies, it looks like for now Katango’s life as a mobile service has been discontinued as a result of this: the app has been removed from Apple’s App Store.

Apture will also be shutting down its existing business.

The company had built up an impressive list of clients for its white-label service (that list includes Scribd, as well as The Financial Times, Reuters (NYSE: TRI), Economist.com, ScientificAmerican, BleacherReport.com, and Times of India). But according to TechCrunch), Google says the white-label services, as well as the plug-ins, will be getting discontinued in the next month or so.

According to the announcement that has now taken over the home page of Apture, the team will now be joining Google Chrome developers.

That implies that Google will be adding Apture’s enhanced search to the Chrome browsing and search experience, but given that Google must be on the lookout for potential new advertising formats as that business matures, I wouldn’t be surprised to see the technology popping up in other parts of the company’s business, too.